Method of and system for regenerating sulphurous acid and waste heat from sulphite cellulose boilers



March 16 1926. 1,576,970

C. HANGLEITER ET AL METHOD OF AND SYSTEM FOR REGENERATING SULPHUROUS ACID'AND WASTE HEAT FROM SULPHITE CELLULOSE BOILERS Filed April 5, 1922 in close proximity to the boiler Patented Mar. 16, 1926.

UNITED STATES. PATENT OFFICE."-

CARL-HANGLEITER, 0F MANNHEIMWA DHQE, AND AnoLE seHNEmEia'oE KEHL- HEIM-ON-TI-IE-DANUBE, GERMANY, ASSIGNORS To zELEsToEEEABmK WALDHOF,

0F MANNHEIM-WALDHOF, GERMANY, A CORPORATION OF GERMANY METHOD OF AND SYSTEM FOR REGENERATING sULrHnRoUs ACID AND WASTE HEAT FROM SULPHITE oELL Los EoILE s.

Application filed April 3,

Z '0 all -1e71'0m it may trance/-11 Be it known that we, Cami .l-lnxu- -LuITEn and AnoLr SCHNEIDER, citizens of Germany, residing. respectively, at Mann- 5 hcim-Valdhof and" Kehlheim-on-the-Dan-" ube, Germany, have invented certain new and useful Improvements in Methods of and Systems for Regenerating Sulphurous Acid and aste Heat from Sulphite Cellulose Boilers; and we do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertaius to make and use the same.

Ourinvcntion relates to improvements in the method of and system for regenerating sulphur dioxide and waste heat from sulphite cellulose boilers,

improvements isto provide a method and a system by means of which a high proportion of the said acid and waste heat is regenerated. \Vith this object in view our invention consists in removing and precipitating the gas and vapor from the sulphite boiler by means of fresh lye. Thereby we are enabled to reduce the pressure of the gas or vapor to a minimum, so that also the loss of acid is reduced to a minimum.

In order that our invention be more clearly understood anexample embodying the same will be described hereinafter, reference being had to the accompanying draw ing showing a preferred system for putting.

the method into 'eifect. In said drawing,

Fig. 1, is a diagrammatical plan view of;

the system, and

Figs. 2 and 3, are side views taken respectively on the lines 22 and 3-3 of Fig. 1.

Referring to the example shown in the figures, our improved system comprises a set of sulphite boilers A, B, Y, and Z, conduits 4 and 5 mounted alongside the set of boilers and adapted to be connected with the top parts of the individual boilers through branch pipes a, 6 y, and 2 and valves a 6, 3 and 2 and valves 11- 12 2 and 2 a tank 7 or 9 for fresh lye adapted to be connected with the conduit 5 respectively through a valve 8 and a valve 10, a pump 11, and a pipe 12, and a tank 14 communicating with both conduits 4 and 5.

and the object of the 1922. Serial No. 549,112.

the-lye flows through the pipe 5 by gravity.

The tank 9 is located below the level of the pipe 5, and the lye is raised into the same by means of the pump 11. It will beunderstood t ha t ordinarily only one of the tanks 7 or 9 is provided, and where both tanks are provided only one of them need be in opera tion at a time.

The operation of the system is as follows: For removing the steam and sulphur dioxide 90 for example from the boilers B and'Y located near the opposite ends of'the conduits 4 and 5. the valves 7) and 7 are opened for establishing connection between the said boilers and the conduit 4, as is known'in the art. Thereby the pressure within the boilers B and Y is reduced say to 2 atn'iospheres. Now the valves 6 and 7 are closed and the valves 1) and 3 opened, so that the boilers are connected through the branch pipes 72, and y, with the conduit 5. Through the conduit 5 there flows cold freshlye from the tank 7 or 9, so that thesteam flowing into the'conduit 5 is immediately condensed and the temperature of the sulphurous acid reduced so far that it is readily absorbed by the. lye. This process is particularly et-.

1 particles of lye. Furthermore, by suddenly cooling the gas and condensing the steam a certain vacuum is produced whereby the gas is rapidly drawn from the boilers by suction. Preferably the vertical part of the conduit 5 which is connected with the tank 14 includes a trap 13. The lye flows into the tank 14, and is finally saturated to the desired degree with sulphur dioxide. Preferably the volume of lyeflowing through the pipe 5 is such that the volume thereof required in a boiler takes up the necessary heat and sulphurous acid. Thereby temperatures are avoided which might cause an objectionable pressure within the conduit 5.

From the foregoing description of the invention it will be understood that the pres sure within the boilers is reduced far beyond the degree attained in systems now in use in which the gas and steam are withdrawn through a conduit similar'to the conduit 4. By connecting all the boilers to a common conduit similar to the conduit 4, the average pressure within the conduit is necessarily high, by reason of the difference of the pressures Within the boilers, the resistance within the long conduit, and the liquid column within the receptacle 14 which must be overcome by the gas, and practically the pressure is not less than 2% atmospheres. This results in a loss of sulphur dioxide and heat. By reducing the pressure in close proximity to the boilers a suction is produced which is primarily transmitted to the individual boilers and is particularly effective by reason of the short length of the branch pipes.

\Ve claim:

1. In a process for regenerating sulphur dioxide and Waste heat from sulphite cellulose boilers, introducing the gas and vapor coming out of the boiler and While still hot at a point in close proximity to the boiler into streaming cold fresh lye.

2. In a process for regenerating sulphur dioxide and Waste heat from sulphite cellulose boilers, introducing the gasand vapor coming out of the boiler and while still hot at a point in close proximity to the boiler into streaming cold fresh lye and introducing said lye into a closed receptacle.

3. In a system for regenerating sulphur dioxide and Waste heat from sulphite cellulose boilers, a conduit for fresh lye lying in close proximity to the boiler, and on the boiler means for discharging gas and vapor directly and While still hot into said conduit.

4. In a system for regenerating sulphur dioxide and waste heat from sulphite cellulose boilers, a conduit for fresh lye, lying in close proximity to the boiler, on the boiler means for discharging gas and vapor directly and while still hot into said conduit, means for continuously supplying fresh lye to the conduit, and means for continuously emptying the conduit.

5. In a system for regenerating sulphur dioxide and Waste heat from sulphite cellulose boilers, a conduit for fresh lye, lying in close proximity to the boiler, on the boiler branch pipes for discharging gas and vapor directly and While still hot into said conduit, a receptacle for continuously supplying fresh lye to the conduit, and a receptacle for continuously emptying the conduit.

6. In a system for regenerating sulphur dioxide and waste heat from sulphite cellulose boilers, a plurality of boilers, a common conduit for fresh lye mounted alongside said boilers in close proximity to the boilers, and on the boilers means for discharging 'gas and vapor directly and while still hot into said conduit.

7. In a system for regenerating sulphur dioxide and Waste heat from sulphite cellulose boilers, a plurality of boilers, a common conduit for fresh lye mounted alongside said boilers in close proximity to the boilers, on the boiler means for discharging gas and vapor directly and While still hot into said conduit, means for continuously supplying fresh lye to the conduit, and means continuously emptying the conduit.

8. In a system for regenerating sulphur dioxide and Waste heat from sulphite cellulose boilers, a plurality of boilers, a common conduit for fresh lye mounted alongside said boilers, in close proximity to the boilers, on the boiler branch pipes for discharging gas and vapor directly and While still hot into said conduit, a receptacle for contlIllOllSlY supplying fresh lye to the conduit, an the conduit.

In testimony whereof We hereunto afiix our signatures.

CARL I-LANGLEITER.

DR. ADOLF SCHNEIDER.

areceptacle for continuously emptying 

